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1.
J Cell Physiol ; 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32048287

RESUMO

High-throughput messenger RNA (mRNA) analysis has become a powerful tool for exploring tumor recurrence or metastasis mechanisms. Here, we constructed a signature to predict the recurrence risk of Stages II and III gastric cancer (GC) patients. A least absolute shrinkage and selection operator method Cox regression model was utilized to construct the signature. Using this method, a 16-mRNA signature was identified to be associated with the relapse-free survival of Stages II and III GCs in training dataset GSE62254 (n = 194). Then this signature was validated in an independent Gene Expression Omnibus cohort GSE26253 (n = 297) and a dataset of The Cancer Genome Atlas (TCGA; n = 235). This classifier could successfully screen out the high-risk Stages II and III GCs in the training cohort (hazard ratio [HR] = 40.91; 95% confidence interval [CI] = 5.58-299.7; p < .0001). Analysis in two independent validation cohorts yielded consistent results (GSE26253: HR = 1.69, 95% CI = 1.17-2.43,; p = .0045; TCGA: HR = 2.01, 95% CI = 1.13-3.56, p = .0146). Cox regression analyses revealed that the risk score derived from this signature was an independent risk factor in Stages II and III GCs. Besides, a nomogram was constructed to serve clinical practice. Through gene set variation analysis, we found several gene sets associated with chemotherapeutic drug resistance and tumor metastasis significantly enriched in high-risk patients. In summary, this 16-mRNA signature can be used as a powerful tool for prognostic evaluation and help clinicians identify high-risk patients.

2.
BMC Genomics ; 21(1): 139, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32041524

RESUMO

BACKGROUND: Lead (Pb) pollution in soil has become one of the major environmental threats to plant growth and human health. Safe utilization of Pb contaminated soil by phytoremediation require Pb-tolerant rapeseed (Brassica napus L.) accessions. However, breeding of new B. napus cultivars tolerance to Pb stress has been restricted by limited knowledge on molecular mechanisms involved in Pb tolerance. This work was carried out to identify genetic loci related to Pb tolerance during seedling establishment in rapeseed. RESULTS: Pb tolerance, which was assessed by quantifying radicle length (RL) under 0 or 100 mg/L Pb stress condition, shown an extensive variation in 472 worldwide-collected rapeseed accessions. Based on the criterion of relative RL > 80%, six Pb-tolerant genotypes were selected. Four quantitative trait loci (QTLs) associated with Pb tolerance were identified by Genome-wide association study. The expression level of nine promising candidate genes, including GSTUs, BCATs, UBP13, TBR and HIPP01, located in these four QTL regions, were significantly higher or induced by Pb in Pb-tolerant accessions in comparison to Pb-sensitive accessions. CONCLUSION: To our knowledge, this is the first study on Pb-tolerant germplasms and genomic loci in B. napus. The findings can provide valuable genetic resources for the breeding of Pb-tolerant B. napus cultivars and understanding of Pb tolerance mechanism in Brassica species.

3.
Mycotoxin Res ; 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32016807

RESUMO

This study was conducted to investigate the exposure to ochratoxin A (OTA) of populations living in Nanjing, China. Plasma samples were collected from 147 healthy adults (age 18-63 years) and analyzed for OTA by a reliable and sensitive ultra-high-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method (limit of detection 0.04 ng/mL). After enzymatic hydrolysis by ß-glucuronidase/arylsulfatase, OTA was detected in 80.9% plasma samples with mean concentration of 0.26 ± 0.59 ng/mL (range 0.04-6.59 ng/mL). The estimated daily intakes of OTA based on plasma concentrations (mean 0.51 ng/kg bw/day, max 12.99 ng/kg bw/day) were lower than the tolerable daily intake published by European Food Safety Authority (EFSA) or Joint FAO/WHO Expert Committee on Food Additives (JFECFA) indicative of rare risks related to the OTA exposure in the investigated area. This study provides a valuable insight on human exposure to OTA in China. Further studies in children and elder people and in adult cohorts from other regions are recommended.

4.
Genes (Basel) ; 11(1)2020 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-31948008

RESUMO

Dilated cardiomyopathy (DCM) is one of the most common causes of heart failure. Several studies have used RNA-sequencing (RNA-seq) to profile differentially expressed genes (DEGs) associated with DCM. In this study, we aimed to profile gene expression signatures and identify novel genes associated with DCM through a quantitative meta-analysis of three publicly available RNA-seq studies using human left ventricle tissues from 41 DCM cases and 21 control samples. Our meta-analysis identified 789 DEGs including 581 downregulated and 208 upregulated genes. Several DCM-related genes previously reported, including MYH6, CKM, NKX2-5 and ATP2A2, were among the top 50 DEGs. Our meta-analysis also identified 39 new DEGs that were not detected using those individual RNA-seq datasets. Some of those genes, including PTH1R, ADAM15 and S100A4, confirmed previous reports of associations with cardiovascular functions. Using DEGs from this meta-analysis, the Ingenuity Pathway Analysis (IPA) identified five activated toxicity pathways, including failure of heart as the most significant pathway. Among the upstream regulators, SMARCA4 was downregulated and prioritized by IPA as the top affected upstream regulator for several DCM-related genes. To our knowledge, this study is the first to perform a transcriptomic meta-analysis for clinical DCM using RNA-seq datasets. Overall, our meta-analysis successfully identified a core set of genes associated with DCM.

5.
J Am Heart Assoc ; 9(2): e014373, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31928175

RESUMO

Background Pediatric hypertension is recognized as an emerging global health concern. Although new guidelines are developed for facilitating clinical management, the reasons for the prevalence of hypertension in children remain unknown. Genetics and environmental factors do not fully account for the growing incidence of pediatric hypertension. Because stable bacterial flora in early life are linked with health outcomes later in life, we hypothesized that reshaping of gut microbiota in early life affects blood pressure (BP) of pediatric subjects. Methods and Results To test this hypothesis, we administered amoxicillin, the most commonly prescribed pediatric antibiotic, to alter gut microbiota of young, genetically hypertensive rats (study 1) and dams during gestation and lactation (study 2) and recorded their BP. Reshaping of microbiota with reductions in Firmicutes/Bacteriodetes ratio were observed. Amoxicillin treated rats had lower BP compared with untreated rats. In young rats treated with amoxicillin, the lowering effect on BP persisted even after antibiotics were discontinued. Similarly, offspring from dams treated with amoxicillin showed lower systolic BP compared with control rats. Remarkably, in all cases, a decrease in BP was associated with lowering of Veillonellaceae, which are succinate-producing bacteria. Elevated plasma succinate is reported in hypertension. Accordingly, serum succinate was measured and found lower in animals treated with amoxicillin. Conclusions Our results demonstrate a direct correlation between succinate-producing gut microbiota and early development of hypertension and indicate that reshaping gut microbiota, especially by depleting succinate-producing microbiota early in life, may have long-term benefits for hypertension-prone individuals.

6.
Endocrinology ; 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31912132

RESUMO

Recent work shows that gut microbial dysbiosis contributes to the risk of obesity in children whose mothers consume a high-fat diet (HFD) during both gestation and lactation or during gestation alone. Obesity predisposes children to developing precocious puberty. However, to date, no study has examined how maternal high-fat diet (MHFD) during lactation regulates the gut microbiota (GM), pubertal timing, and fertility of offspring. Here, we found that MHFD during lactation markedly altered the GM of offspring. The pups developed juvenile obesity, early puberty, irregular estrous cycles, and signs of disrupted glucose metabolism. Remarkably, permitting coprophagia between MHFD and maternal normal chow offspring successfully reversed the GM changes as well as early puberty and insulin insensitivity. Our data suggest that microbial reconstitution may prevent or treat early puberty associated with insulin resistance.

8.
Plant Physiol Biochem ; 146: 220-230, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31760343

RESUMO

Flowering time is regulated by biotic and abiotic stresses and affected by the ambient temperature. For chrysanthemum, a low ambient growth temperature can cause a flowering delay, which limits the annual commercial production. Therefore, it is important to improve the low-temperature flowering capability of chrysanthemum through genetic modifications. Here, we isolated a natural variation of a CRT/DRE-binding factor (CBF/DREB) 3 gene, CRAP2, from the Arabidopsis thaliana accession Condara (190AV) that encodes a stop codon at position 151 of the CBF3 protein. Unlike AtCBF3, the overexpression AtCRAP2 in Arabidopsis did not cause detectable growth retardation nor delayed flowering and it conferred cold tolerance. The cold-inducible expression of AtCRAP2 in chrysanthemum promoted flowering under short-day conditions with a low 15 °C nighttime temperature. RNA-sequencing of rd29A:AtCRAP2 and qRT-PCR assays of flowering time-related genes and AtCRAP2 expressed at an ambient temperature revealed that AtCRAP2 positively affected SOC1 and FTL3, thereby promoting flowering under low temperature stress and short-day conditions. These results indicate that DREB genes can be used in the genetic engineering of crop plants without accompanying negative effects by modifying the encoded proteins' C termini.

9.
Physiol Genomics ; 52(1): 1-14, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31762410

RESUMO

Here we postulate that the heritability of complex disease traits previously ascribed solely to the inheritance of the nuclear and mitochondrial genomes is broadened to encompass a third component of the holobiome, the microbiome. To test this, we expanded on the selectively bred low capacity runner/high capacity runner (LCR/HCR) rat exercise model system into four distinct rat holobiont model frameworks including matched and mismatched host nuclear and mitochondrial genomes. Vertical selection of varying nuclear and mitochondrial genomes resulted in differential acquisition of the microbiome within each of these holobiont models. Polygenic disease risk of these novel models were assessed and subsequently correlated with patterns of acquisition and contributions of their microbiomes in controlled laboratory settings. Nuclear-mitochondrial-microbiotal interactions were not for exercise as a reporter of health, but significantly noted for increased adiposity, increased blood pressure, compromised cardiac function, and loss of long-term memory as reporters of disease susceptibility. These findings provide evidence for coselection of the microbiome with nuclear and mitochondrial genomes as an important feature impacting the heritability of complex diseases.

10.
Chem Commun (Camb) ; 56(3): 478-481, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31829340

RESUMO

Janus membranes (JMs) with hierarchical micro/nanostructures were constructed by unilaterally electro-spinning/spraying a hydrophobic polymer on various hydrophilic porous substrates for liquid manipulation/rectification. The membrane geometry and liquid transport behaviors can be delicately tuned. Our novel universal strategy can be extended to diverse hydrophobic porous substrates.

11.
Sci Total Environ ; 704: 135398, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31836228

RESUMO

The differences of PBDE absorption, accumulation, and metabolism in different cultivars of the same crop are rarely explored. This study used 14C tracing to fully demonstrate the uptake and transformation of soil-borne BDE209 in three rice cultivars, including two indica (HHZ and YD1) and one japonica cultivars (NJ3). Results showed that about 6.9, 17.2, and 17.4% of the applied 14C-BDE209 were transformed to 14C-metabolites in soils planted with HHZ, YD1, and NJ3, respectively. The 14C-BDE209 and its 14C-metabolites in soil could be absorbed by the rice and gradually transported to its root, stem, leaf, and grain, with the total whole-plant uptake of 8.52, 4.55 and 3.43 nmol for HHZ, YD1, and NJ3, respectively. The cultivar of HHZ had the greatest whole-plant 14C absorption but the lowest ΣPBDEs residues in its grain, with the ΣPBDEs of 421.8, 454.2 and 967.0 ng g-1 for HHZ, YD1, and NJ3, respectively. BDE-209 accounted for 90%, 31% and 50% of the ΣPBDEs in the grain from HHZ, YD1, and NJ3, respectively. The estimated daily intake (EDI) amounts of ΣPBDEs were 928, 1056, and 2675 ng kg-1 bw d-1 via consuming rice grains from HHZ, YD1, and NJ3, respectively, which were below the safe threshold limits for human consumption. This study proved the different BDE-209 absorption, accumulation and transformation in different rice cultivars, which potentially suggests the need of considering cultivar differences in assessing the dietary risks of PBDEs.

12.
J Comput Chem ; 41(5): 415-420, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31329318

RESUMO

The double electron-electron resonance (DEER) is a powerful structural biology technique to obtain distance information in the range of 18 to 80 å by measuring the dipolar coupling between two unpaired electron spins. The distance distributions obtained from the experiment provide valuable structural information about the protein in its native environment that can be exploited using restrained ensemble molecular dynamics (reMD) simulations. We present a new tool DEER Facilitator in CHARMM-GUI that consists of two modules Spin-Pair Distributor and reMD Prepper to setup simulations that utilize information from DEER experiments. Spin-Pair Distributor provides a web-based interface to calculate the spin-pair distance distribution of labeled sites in a protein using MD simulations. The calculated distribution can be used to guide the selection of the labeling sites in experiments as well as validate different protein structure models. reMD Prepper facilities the setup of reMD simulations using different types of spin labels in four different environments including vacuum, solution, micelle, and bilayer. The applications of these two modules are demonstrated with several test cases. Spin-Pair Distributor and reMD Prepper are available at http://www.charmm-gui.org/input/deer and http://www.charmm-gui.org/input/deerre. DEER Facilitator is expected to facilitate advanced biomolecular modeling and simulation, thereby leading to an improved understanding of the structure and dynamics of complex biomolecular systems based on experimental DEER data. © 2019 Wiley Periodicals, Inc.

13.
Nat Prod Res ; 34(2): 225-232, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30580619

RESUMO

One new aryldihydronaphthalene-type lignan (1) together with eight known lignans (2-4, 7-11) as well as two caffeic-acid dimers (5, 6) were isolated from an ethanol extract of the whole plant of Corispermum mongolicum Iljin (Chenopodiaceae). The chemical structures of these compounds were determined from 1D and 2D NMR and HR-ESI-MS spectra, and results were compared with data from the literature. This study is the first demonstration of nine compounds (2 and 4-11) isolated from the Chenopodiaceae family, with one of these (3) from the genus Corispermum. Anti-inflammatory effects of the isolated compounds were evaluated in terms of inhibition of production of nitric oxide, tumour necrosis factor-α, and interleukin-6 in lipopolysaccharide-induced RAW 264.7 cells.

14.
J Cell Mol Med ; 24(2): 1750-1759, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31876059

RESUMO

Stomach cancer is the fourth most common cancer worldwide. Identification of novel molecular therapeutic targets and development of novel treatments are critical. Against a panel of gastric carcinoma cell lines, the activity of 2-(4-amino-3-methylphenyl)-5-fluorobenzothiazole (5F 203) was investigated. Adopting RT-PCR, Western blot and immunohistochemical techniques, we sought to determine molecular pharmacodynamic (PD) markers of sensitivity and investigate arylhydrocarbon (AhR) receptor-mediated signal transduction activation by 5F 203. Potent (IC50  ≤ 0.09 µmol/L), selective (>250-fold) in vitro antitumour activity was observed in MKN-45 and AGS carcinoma cells. Exposure of MKN-45 cells to 5F 203 triggered cytosolic AhR translocation to nuclei, inducing CYP1A1 (>50-fold) and CYP2W1 (~20-fold) transcription and protein (CYP1A1 and CYP2W1) expression. G2/M arrest and γH2AX expression preceded apoptosis, evidenced by PARP cleavage. In vivo, significant (P < .01) 5F 203 efficacy was observed against MKN-45 and AGS xenografts. In mice-bearing 5F 203-sensitive MKN-45 and 5F 203-insensitive BGC-823 tumours in opposite flanks, CYP1A1, CYP2W1 and γH2AX protein in MKN-45 tumours only following treatment of mice with 5F 203 (5 mg/kg) revealed PD biomarkers of sensitivity. 5F 203 evokes potent, selective antitumour activity in vitro and in vivo in human gastric cancer models. It triggers AhR signal transduction, CYP-catalysed bioactivation to electrophilic species causing lethal DNA double-strand breaks exclusively in sensitive cells. 5F 203 represents a novel therapeutic agent with a mechanism of action distinct from current clinical drugs, exploiting novel molecular targets pertinent to gastric tumourigenesis: AhR, CYP1A1 and CYP2W1. PD markers of 5F 203 sensitivity that could guide patient selection have been identified.

15.
J Gynecol Oncol ; 31(1): e8, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31788998

RESUMO

OBJECTIVE: The purpose of this study was to analyze the impact of surgery of primary sites on stage IVB cervical cancer patients from a population-based database, the Surveillance, Epidemiology and End Results (SEER). METHODS: Propensity score matching was performed to minimize heterogeneity in patient between with-surgery group and without-surgery group. Clinicopathological characteristics were compared using the χ² or Fisher's exact test. Survival analysis included the Kaplan-Meier method, log-rank test, and Cox proportional hazards model. RESULTS: Between 2010-2015, a total of 1,139 International Federation of Gynecology and Obstetrics (FIGO) stage IVB cervical cancer patients receiving chemoradiotherapy (CRT) were included in this retrospective study. Within post-matching cohort, the median duration of overall survival (OS) in stage IVB cervical cancer patients receiving CRT was 22 months. The overall 5-year survival rate was 25.7%. The increasing American Joint Committee on Cancer T stage (T1 vs. T2, p=0.033, hazard ratio [HR]=1.79, 95% confidence interval [CI]=1.05-3.05; T1 vs. T3, p=0.003, HR=2.20, 95% CI=1.31-3.67; T1 vs. T4, p=0.037, HR=2.75, 95% CI=1.06-7.12) and visceral metastasis (with vs. without, p=0.038, HR=1.60, 95% CI=1.03-2.49) was reported as independent risk factors of OS. Surgery of primary sites combined with CRT tended to prolong the survival of stage IVB cervical cancer patients (p<0.001, HR=0.36, 95% CI=0.21-0.61) compared with CRT, especially for patients without visceral metastasis (p=0.005, HR=0.31, 95% CI=0.14-0.70). CONCLUSIONS: In conclusion, patients with stage IVB cervical cancer may achieve their best outcomes through CRT combined with surgery of primary sites. However, it deserves large scale prospective clinical trials to confirm.

16.
Cancer Med ; 9(3): 988-998, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31846222

RESUMO

OBJECTIVE: Stage I-II uterine papillary serous carcinoma (UPSC) has aggressive biological behavior and leads to poor prognosis. However, clinicopathologic risk factors to predict cancer-specific survival of patients with stage I-II UPSC were still unclear. This study was undertaken to develop a prediction model of survival in patients with early-stage UPSC. METHODS: Using Surveillance, Epidemiology, and End Results (SEER) database, 964 patients were identified with International Federation of Gynecology and Obstetrics (FIGO) stage I-II UPSC who underwent at least hysterectomy between 2004 and 2015. By considering competing risk events for survival outcomes, we used proportional subdistribution hazards regression to compare cancer-specific death (CSD) for all patients. Based on the results of univariate and multivariate analysis, the variables were selected to construct a predictive model; and the prediction results of the model were visualized using a nomogram to predict the cancer-specific survival and the response to adjuvant chemotherapy and radiotherapy of stage I-II UPSC patients. RESULTS: The median age of the cohort was 67 years. One hundred and sixty five patients (17.1%) died of UPSC (CSD), while 8.6% of the patients died from other causes (non-CSD). On multivariate analysis, age ≥ 67 (HR = 1.45, P = .021), tumor size ≥ 2 cm (HR = 1.81, P = .014) and >10 regional nodes removed (HR = 0.52, P = .002) were significantly associated with cumulative incidence of CSD. In the age ≥67 cohort, FIGO stage IB-II was a risk factor for CSD (HR = 1.83, P = .036), and >10 lymph nodes removed was a protective factor (HR = 0.50, P = .01). Both adjuvant chemotherapy combined with radiotherapy and adjuvant chemotherapy alone decreased CSD of patients with stage I-II UPSC older than 67 years (HR = 0.47, P = .022; HR = 0.52, P = .024, respectively). The prediction model had great risk stratification ability as the high-risk group had higher cumulative incidence of CSD than the low-risk group (P < .001). In the high-risk group, patients with post-operative adjuvant chemoradiotherapy had improved CSD compared with patients who did not receive radiotherapy nor chemotherapy (P = .037). However, there was no such benefit in the low-risk group. CONCLUSION: Our prediction model of CSD based on proportional subdistribution hazards regression showed a good performance in predicting the cancer-specific survival of early-stage UPSC patients and contributed to guide clinical treatment decision, helping oncologists and patients with early-stage UPSC to decide whether to choose adjuvant therapy or not.

17.
Sci Total Environ ; 698: 134315, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31783453

RESUMO

Bioaerosol in the atmosphere plays a very important role in environment and public health. To forecast the bioaerosol concentration, the correlation between bioaerosol concentration and meteorological factors was discussed, and a Back Propagation (BP) neural network with Principal Component Analysis (PCA) method was utilized in this study. The proposed method works in three steps. The first step is to compute the correlation between bioaerosol concentration and meteorological factors, which consists of analyzing correlation and selecting meteorological factors applied to the study of forecast model. The second step is to use PCA analysis to reduce the dimensions of meteorological dataset. The third step is to use BP neural network, setting up, training BP neural network and proving the feasibility of forecast model included. The results of our model in forecasting bioaerosol concentration show 10.55% of average relative error, 2.80 pieces/L (pcs/L) of average absolute error, and 84.01 grade of forecast accuracy, providing a promising model for the forecasting of bioaerosol concentration.


Assuntos
Aerossóis/análise , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental/métodos , Atmosfera , Conceitos Meteorológicos
18.
PeerJ ; 7: e8064, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31824757

RESUMO

Phenylalanine ammonia lyase (PAL) plays an important role in the biosynthesis of secondary metabolites regulating plant growth response. To date, the evolutionary history of the PAL family in Rosaceae plants remains unclear. In this study, we identified 16 PAL homologous genes in five Rosaceae plants (Pyrus bretschneideri, Fragaria vesca, Prunus mume, Prunus persica, and Malus × domestica). We classified these PALs into three categories based on phylogenetic analysis, and all PALs were distributed on 13 chromosomes. We tracked gene duplication events and performed sliding window analysis. These results revealed the evolution of PALs in five Rosaceae plants. We predicted the promoter of the PbPALs by PLANT CARE online software, and found that the promoter region of both PbPAL1 and PbPAL3 have at least one AC element. The results of qRT-PCR analysis found that PbPAL1 and PbPAL2 were highly expressed in the stems and roots, while expression level of PbPAL3 was relatively low in different tissues. The expression of PbPAL1 and PbPAL2 increased firstly and then decreased at different developmental periods of pear fruit. Among them, the expression of PbPAL1 reached the highest level 55 days after flowering. Three PbPALs were induced by abiotic stress to varying degrees. We transfected PbPAL1 and PbPAL2 into Arabidopsis thaliana, which resulted in an increase in lignin content and thickening of the cell walls of intervascular fibres and xylem cells. In summary, this research laid a foundation for better understanding the molecular evolution of PALs in five Rosaceae plants. Furthermore, the present study revealed the role of PbPALs in lignin synthesis, and provided basic data for regulating lignin synthesis and stone cells development in pear plants.

19.
Plants (Basel) ; 8(12)2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31810261

RESUMO

Seed, resulting from reproductive development, is the main nutrient source for human beings, and reproduction has been intensively studied through genetic, molecular, and epigenetic approaches. However, how different epigenetic pathways crosstalk and integrate to regulate seed development remains unknown. Here, we review the recent progress of epigenetic changes that affect chromatin structure, such as DNA methylation, polycomb group proteins, histone modifications, and small RNA pathways in regulating plant reproduction. In gametogenesis of flowering plants, epigenetics is dynamic between the companion cell and gametes. Cytosine DNA methylation occurs in CG, CHG, CHH contexts (H = A, C, or T) of genes and transposable elements, and undergoes dynamic changes during reproduction. Cytosine methylation in the CHH context increases significantly during embryogenesis, reaches the highest levels in mature embryos, and decreases as the seed germinates. Polycomb group proteins are important transcriptional regulators during seed development. Histone modifications and small RNA pathways add another layer of complexity in regulating seed development. In summary, multiple epigenetic pathways are pivotal in regulating seed development. It remains to be elucidated how these epigenetic pathways interplay to affect dynamic chromatin structure and control reproduction.

20.
Transplant Proc ; 51(10): 3474-3480, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31810510

RESUMO

Patients with craniocerebral trauma often have intestinal mucosal dysfunction, and the claudin1 protein plays an important role in intestinal mucosal function. Our previous work has shown that the expression of microRNA-155 (miR-155) in the peripheral blood of patients with craniocerebral trauma is decreased. Animal experiments also suggest that the expression of miR-155 is increased in the intestinal mucosa of mice with brain injury and the expression of claudin1 is decreased. We recruited 56 samples (35 patients with traumatic brain injury [TBI] and 21 patients without history of head trauma) to detect the expression of miR-155 on claudin1 regulation by quantitative polymerase chain reaction, reverse transcriptase polymerase chain reaction, and so on. We also used the receiver operating characteristic curve (ROC) to further evaluate the diagnostic value of the 2 biomarkers. From the results, we found that the expression level of miR-155 and claudin1 in the case group was lower than that in the control group. Human miR-155 (Hsa-miR-155) may positively regulate intestinal mucosal function by inhibiting the expression of claudin1, leading to intestinal mucosal barrier dysfunction. Combining the ROC curve data, the results further prove that miR-155 and claudin1 might be the new clinical diagnostic markers and treatment targets for the intestinal mucosal barrier dysfunction after TBI.

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